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Related papers: Active galactic nuclei catalog from the AKARI NEP …

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We present the results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a cross-correlation of the ROSAT all sky survey (RASS) bright source…

Astrophysics · Physics 2007-05-23 K. Bischoff , W. Pietsch , T. Boller , S. Döbereiner , W. Kollatschny , H. -U. Zimmermann

Reliably identifying active galactic nuclei (AGNs) in dwarf galaxies is key to understanding black hole demographics at low masses and constraining models for black hole seed formation. Here we present Chandra X-ray Observatory observations…

Astrophysics of Galaxies · Physics 2022-06-24 Lilikoi J. Latimer , Amy E. Reines , Kevin N. Hainline , Jenny E. Greene , Daniel Stern

We present ELDAR, a new method that exploits the potential of medium- and narrow-band filter surveys to securely identify active galactic nuclei (AGN) and determine their redshifts. Our methodology improves on traditional approaches by…

We propose a new method for identifying active galactic nuclei (AGN) in low mass ($\rm M_*\leq10^{10}M_\odot$) galaxies. This method relies on spectral energy distribution (SED) fitting to identify galaxies whose radio flux density has an…

This paper presents a 610 MHz radio survey covering 1.94 square degrees around the North Ecliptic Pole (NEP), which includes parts of the AKARI (ADF-N) and Euclid, Deep Fields North. The median 5-sigma sensitivity is 28 microJy beam per…

Spitzer IRAC selection is a powerful tool for identifying luminous AGN. For deep IRAC data, however, the AGN selection wedges currently in use are heavily contaminated by star-forming galaxies, especially at high redshift. Using the large…

We present a study of Spitzer/IRAC and X-ray active galactic nuclei (AGNs) selection techniques in order to quantify the overlap, uniqueness, contamination, and completeness of each. We investigate how the overlap and possible contamination…

We discuss the very different methods in each wavelength band for selecting and finding Active Galactic Nuclei (AGN). We briefly review the history of the different techniques for finding AGN and compare and contrast the advantages and…

Astrophysics · Physics 2016-01-27 Richard Mushotzky

Using Spitzer-IRS spectroscopy, we investigate the ubiquity of Active Galactic Nuclei (AGN) in a complete (~94%), volume-limited sample of the most bolometrically-luminous galaxies (L_IR > (0.3-20) x 10^10 L_sun) to D < 15 Mpc. Our analyses…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Andy Goulding , Dave Alexander

We aim to study the effect of environment on the presence and fuelling of Active Galactic Nuclei (AGN) in massive galaxy clusters. We explore the use of different AGN detection techniques with the goal of selecting AGN across a broad range…

Astrophysics of Galaxies · Physics 2015-06-05 Alison J. Klesman , Vicki L. Sarajedini

She et al. (Paper I) assembled a catalog of nearby galaxies observed with the Chandra X-ray observatory, by cross-matching galaxies in the NASA Extragalactic Database (NED) within 50 Mpc and the Chandra archive. That sample has enabled…

Astrophysics of Galaxies · Physics 2020-08-06 Sheng Bi , Hua Feng , Luis C. Ho

Machine-learning (ML) algorithms will play a crucial role in studying the large datasets delivered by new facilities over the next decade and beyond. Here, we investigate the capabilities and limits of such methods in finding galaxies with…

Instrumentation and Methods for Astrophysics · Physics 2019-08-22 Andreas L. Faisst , Abhishek Prakash , Peter L. Capak , Bomee Lee

Aims. We present an 8-band (u*, g', r', i', z', Y, J, Ks) optical to NIR deep photometric catalog based on the observations made with MegaCam and WIRCam at CFHT, and compute photometric redshifts, zp in the North Ecliptic Pole (NEP) region.…

The detection of X-ray emission constitutes a reliable and efficient tool for the selection of Active Galactic Nuclei (AGNs), although it may be biased against the most heavily absorbed AGNs. Simple mid-IR broad-band selection criteria…

Astrophysics of Galaxies · Physics 2020-05-06 E. Pouliasis , G. Mountrichas , I. Georgantopoulos , A. Ruiz , M. Yang , A. Z. Bonanos

We present a new sample of active galactic nuclei (AGNs) identified using the catalog of the AKARI Mid-infrared(MIR) All-Sky Survey. Our MIR search has an advantage in detecting AGNs that are obscured at optical wavelengths due to…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-24 S. Oyabu , D. Ishihara , M. Malkan , H. Matsuhara , T. Wada , T. Nakagawa , Y. Ohyama , Y. Toba , T. Onaka , S. Takita , H. Kataza , I. Yamamura , M. Shirahata

We searched in the public archive of the Chandra X-ray Observatory as of March 2016 and assembled a sample of 719 galaxies within 50 Mpc with ACIS observations available. By cross-correlation with the optical or near-infrared nuclei of…

Astrophysics of Galaxies · Physics 2017-02-08 Rui She , Luis C. Ho , Hua Feng

Reliable, versatile galaxy activity diagnostics are essential for understanding galaxy evolution. Traditional methods frequently necessitate extensive preprocessing, such as starlight subtraction and emission line deblending (e.g.,…

Astrophysics of Galaxies · Physics 2026-02-25 C. Daoutis , A. Zezas , E. Kyritsis , K. Kouroumpatzakis , P. Bonfini

Active Galactic Nuclei (AGNs) are characterized by emission of radiation over more than 10 orders of magnitude in frequency. Therefore, the execution of extensive surveys of the sky, with different types of detectors, is providing the…

Understanding the co-evolution of supermassive black holes (SMBHs) and their host systems requires a comprehensive census of active galactic nuclei (AGN) behavior across a wide range of redshift, luminosity, obscuration level and galaxy…

An empirical forward-modeling framework is developed to interpret the multiwavelength properties of Active Galactic Nuclei (AGN) and provide insights into the overlap and incompleteness of samples selected at different parts of the…

High Energy Astrophysical Phenomena · Physics 2020-10-21 Antonis Georgakakis , Angel Ruiz , Stephanie M. LaMassa